The improvement of image processing technique enables an image processing system to output a high-quality image.
For example, printing equipment such as a printer, a copy machine, a facsimile machine, a MFP (Multi Function Peripheral) and the like is able to perform high-quality printing or photographic printing.
Image data composed of multi level pixels is inputted to such printing equipment. Then, the printing equipment performs printing or photographic printing on the basis of the image data.
In cases such as where a plurality of copies of inputted image data is needed to be printed, such printing equipment stores the image data in an internal memory temporarily. Then, the printing equipment reads the image data from the internal memory and performs printing operation.
Image data consumes the memory capacity of printing equipment largely when the data is left uncompressed. For this reason, printing equipment stores image data in a memory after the data is compressed by a predetermined method using an image coding system such as JPEG (Joint Photographic Experts Group) or the like. When image data is printed, the printing equipment reads compressed image data from the memory. After that, the printing equipment decompresses the compressed image data and performs printing processing using the decompressed image data.
In Japanese Patent Application Laid-Open No. 2002-084425, there is described a multi level image data compression device in which inputted multi level image data is binary-compressed without changing the form of the original image data when there are a little intermediate image intensity portions in the image data.
In Japanese Patent Application Laid-Open No. 2004-236295, a technology of an image processing apparatus which uses a bit plane coding technique which is one of the features of the compression coding by the JPEG2000 algorithm is described.
In Japanese Patent Application Laid-Open No. 2004-312773, there is described an image encoding apparatus which performs bit plane compression.
In Japanese Patent Application Laid-Open No. 2006-343831, an image processing apparatus which determines an attribute of an image for each block is described.
In Japanese Patent Application Laid-Open No. 2007-088968, there is described an image output system using attribute information.